Plaster or Plastic?

You may have heard Z Corp’s announcement today about ZBuilder Ultra, a new rapid prototyping system for producing high resolution prototype parts. This new system produces highly accurate thin walled plastic parts with smooth surface finishes. Some of you may be wondering if this system could be used for AEC models. Good question. In my travels around the world to various architectural firms, I occasionally see plastic models on display mixed among the wood, chipboard, and Plexiglas models in lobby exhibits. When I ask why that material was chosen, I get a variety of responses. Some say that their service bureau had an SLS or SLA machine, so this is what they delivered. Others say that clients perceive the plastic models to be more durable for long term display.

While architects are happy to pass on their costs to the client for a one-time presentation model, most agree that there is no substitute for inexpensive, fast turnaround composite material (gypsum-based “plaster”) models during the early conceptual design and design development process. These are the times during the project when designers want immediate feedback and designs change quickly. How does your firm incorporate physical models into their design process, and what materials are preferred and why?